Added entry and exit

include/etl/sfsm.h

@@ -0,0 +1,187 @@
+/******************************************************************************
+The MIT License(MIT)
+
+Embedded Template Library.
+https://github.com/ETLCPP/etl
+https://www.etlcpp.com
+
+Copyright(c) 2018 jwellbelove
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files(the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions :
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+******************************************************************************/
+
+#ifndef ETL_LWFSM_INCLUDED
+#define ETL_LWFSM_INCLUDED
+
+#include <stdint->h>
+
+#include "etl/nullptr.h"
+
+namespace etl
+{
+  //***************************************************************************
+  /// Simple State Machine
+  //***************************************************************************
+  template <typename TObject>
+  class sfsm
+  {
+  public:
+
+    typedef uint32_t state_id_t;
+    typedef uint32_t event_id_t;
+
+    //*************************************************************************
+    /// Transition definition
+    //*************************************************************************
+    struct transition
+    {
+      transition(const event_id_t event_id_,
+                 const state_id_t current_state_id_,
+                 const state_id_t next_state_id_,
+                 void (TObject::* const action_)() = nullptr,
+                 bool (TObject::* const guard_)()  = nullptr)
+        : event_id(event_id_),
+          current_state(current_state_),
+          nextState(next_state_),
+          action(action_),
+          guard(guard_)
+      {
+      }
+
+      const event_id_t event_id;
+      const state_id_t current_state_id;
+      const state_id_t next_state_id;
+      void (TObject::* const action)();
+      bool (TObject::* const guard)();
+    };
+
+    //*************************************************************************
+    /// State definition
+    //*************************************************************************
+    struct state
+    {
+      state(const state_id_t state_id_,
+            void (TObject::* const on_enter_)() = nullptr,
+            void (TObject::* const on_exit_)() = nullptr)
+        : state_id(state_id_),
+          on_enter_(on_enter_),
+          on_exit(on_exit_)
+      {
+      }
+
+      state_id_t state_id;
+      void (TObject::* const on_enter)();
+      void (TObject::* const on_exit)();
+    };
+
+    //*************************************************************************
+    ///
+    //*************************************************************************
+    template <const uint32_t TRANSITION_TABLE_SIZE, const uint32_t STATE_TABLE_SIZE>
+    sfsm(TObject& object_, 
+                  const transition(&transition_table_)[TRANSITION_TABLE_SIZE], 
+                  const enter_exit(&state_table_)[STATE_TABLE_SIZE], 
+                  const state_id_t state_id_)
+      : object(object_),        
+        current_state_id(state_id_),
+        transition_table(&transition_table_[0]),
+        transition_table_size(TRANSITION_TABLE_SIZE)
+        state_table(&state_table_[0]),
+        state_table_size(ENTER_EXIT_TABLE_SIZE)
+    {
+    }
+
+    //*************************************************************************
+    ///
+    //*************************************************************************
+    state_id_t get_state() const
+    {
+      return current_state;
+    }
+
+    //*************************************************************************
+    ///
+    //*************************************************************************
+    void process_event(const event_id_t event_id)
+    {
+      // Scan the transition table.
+      transition* transition_table_begin = transition_table;
+      transition* transition_table_end   = transition_table + transition_table_size;
+
+      transition* t = std::find_if(transition_table_begin,
+                                   transition_table_end,
+                                   is_transition(event_id, current_state_id));
+
+      // Found an entry?
+      if (t != transition_table_end)
+      {
+        // Shall we execute the transition?
+        if ((t->guard == nullptr) || ((object->*t->guard)()))
+        {
+          // Are we moving to a new state?
+          const bool to_new_state = (current_state_id != t->next_state_id);
+
+          state* state_table_begin = state_table;
+          state* state_table_end   = state_table + state_table_size;
+
+          // See if we have a state entry.
+          state* s = std::find_if(state_table_begin,
+                                  state_table_end,
+                                  is_state(current_state_id));
+
+          // If the current state has an 'on_exit' and we are changing states, then call it.
+          if (to_new_state && (s != state_table_end) && (s->on_exit != nullptr))
+          {
+            (object->*(s->on_exit))();
+          }
+
+          // Shall we execute the action?
+          if (t->action != nullptr)
+          {
+            (object->*t->action)();
+          }
+
+          // See if we have a state entry.
+          s = std::find_if(state_table_begin,
+                           state_table_end,
+                           is_state(t->next_state_id));
+
+          // If the new state has an 'on_entry' and we are changing states, then call it.
+          if (to_new_state && (s != state_table_end) && (s->on_exit != nullptr))
+          {
+            (object->*(s->on_entry))();
+          }
+
+          current_state_id = t->next_state_id;
+        }
+      }
+    }
+
+  private:
+
+    state_id_t        current_state_id;      ///< The current state id.
+    TObject&          object;                ///< The object that supplies codition and action member functions
+    const transition* transition_table;      ///< The table of transitions.
+    const uint32_t    transition_table_size; ///< The size of the transition table.
+    const state*      state_table;           ///< The table of transitions.
+    const uint32_t    state_table_size;      ///< The size of the transition table.
+  };
+}
+
+#endif

test/vs2017/etl.vcxproj

@@ -371,7 +371,7 @@
     <ClInclude Include="..\..\include\etl\fsm.h" />
     <ClInclude Include="..\..\include\etl\fsm_generator.h" />
     <ClInclude Include="..\..\include\etl\largest_generator.h" />
-    <ClInclude Include="..\..\include\etl\state_machine.h" />
+    <ClInclude Include="..\..\include\etl\sfsm.h" />
     <ClInclude Include="..\..\include\etl\math_constants.h" />
     <ClInclude Include="..\..\include\etl\memory_model.h" />
     <ClInclude Include="..\..\include\etl\message.h" />

test/vs2017/etl.vcxproj.filters

@@ -693,7 +693,7 @@
     <ClInclude Include="..\..\include\etl\atomic\atomic_llvm_sync.h">
       <Filter>ETL\Utilities\Atomic</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\include\etl\state_machine.h">
+    <ClInclude Include="..\..\include\etl\sfsm.h">
       <Filter>ETL\Frameworks</Filter>
     </ClInclude>
   </ItemGroup>